Subject: [atoca] The future of atoca

From: Martin Thomson <[email-masked]>
Date: Thu, 19 Jul 2012 17:45:10 -0700

This working group has been quiet for extended periods for a long time
now.  The chairs are concerned that there are too few participants who
are interested in furthering the work of the group for the group to be
viable.

For the Vancouver IETF we would like to address the question of
closing the working group.

If we are to keep the working group open, a number of people would
have to come forward between now and the scheduled meeting time.
These people would not only express interest, but also demonstrate a
firm commitment to contribute to the goals of the group.

On the other hand, if we conclude that closing the working group is
preferable, we then need to decide what to do with the products of
this working group, such as they are.  The working group has one
adopted draft, but there have also been several individual
submissions.

Then, in either case - for the continued success of the group, or
merely for posterity - thoughts on whether this effort would have
succeeded and the conditions under which it might have succeeded/could
succeed would be of great interest.  Would a tighter focus in a
particular area have made this more feasible?

To that end, the chairs propose that we address this issue in
Vancouver.  A draft agenda containing this item has been posted.

--atoca Chairs

---

From: "'Mark Wood'" <[email-masked]>
Date: Fri, 20 Jul 2012 11:37:20 +0100

Friends,

I would like to say that the work of ATOCA is very much needed. This is
absolutely NOT the time to put it on the back burner.  

I have not been intervening in the matters at hand because the members have
been doing the job well enough that I am satisfied with what is being done.
My sponsors DRCF have small resources so I don't travel to a conf on their
buck unless there is a good reason for me to be there in physical person,
and I have been well satisfied so far. 

Meantime, in the cellular world, the Multicast Address Harmonisation
recommendation at ITU-T SG2 and has stopped without any agreement on further
work at the ITU other than a possible 'Supplement', so we don't need to wait
for any recommendations to appear from them. 

However the 3GPP HAS done all that is needed, and the 3GPP has published its
latest revision of the standard affecting public warning (3GPP 023.041
V11.1.0) (section 9) for GSM, UMTS and LTE, and this work is moving on very
rapidly and to the satisfaction of nearly everyone. 

Harmonisation has been achieved between the USA CMAS/WEA system, the South
Korean system and the international ETSI 102-900 system EU-ALERT, so I am
very satisfied with the work that 3GPP has done and I don' plan to replicate
any of it elsewhere. 

Member states also seem satisfied with the options that 3GPP have presented
them with, I don't see anyone trying to re invent a different wheel, in fact
nations are building chariots now. 

Now that the matter is settled in the cellular world and the wheels are
being put up on the wagons, its time to look at the IP world so that we have
complementary offering. 

My MSc thesis project for this coming year (I am 'bogged down' with the
London Olympics logistics at the moment) is to study the matter of provision
of Public Warning systems over multicast technology in IP4 and IP6. Is it an
appropriate solution at all? If so we need to see if there are any gaps in
the technology, that need addressing, or if it is OK as is. My current
feeling is that there are three ways of dealing with this issue.

1 Emulate a 'PWS like' system rather similar to 3GPP solution, (simplest,
much of this work is already 'running code').
2 Have a completely different philosophy more applicable to IP networks.
3 A hybrid solution cherry picking the best of both.  

I am keeping an open mind on the matter at the moment, but I hope to have it
very clearly crystallised by this time next year.

So, I would implore the ATOCA to keep open while we further discuss what
more research and recommendations will be needed going forward, I don't
think we have looked at all of these matters just yet and the starting gun
has only just fired on this important matter. If we find that we don't need
any more recommendations, then we can close the matter for now. 

As soon as the Olympics are done with, I will be focusing on this matter and
I assure you that I will be providing a lot of quality input to this group
from now on. Please, keep this focus group going, and there is a noble and
worthy reward at the end of the line, we will all have reason to be proud of
this work if we see it through.  

Mark Wood DRCF.

---

From: "DRAGE, Keith (Keith)" <[email-masked]>
Date: Fri, 20 Jul 2012 12:40:21 +0200

As yet again, I cannot get to the ATOCA session because I am chairing a session at the same time, I'll comment on list.

I don't see enough momentum to have a working group on this subject. The idea of a working group is to gain a certain amount of consensus round a subject before submitting a document to the IETF last call process. So there is no point writing drafts which essentially only the authors comment on in the WG. The WG has had more than adequate time to gather that momentum if it existed.

Given that, if the authors of documents really want to proceed, they might as well put the documents straight into the individual submission process (or else abandon them).

There is no point in continuing with the working group as it is adding nothing to the process of gaining IETF consensus.

Keith

> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]] On Behalf Of
> Martin Thomson
> Sent: 20 July 2012 01:45
> To: [email-masked]
> Subject: [atoca] The future of atoca
> 
> _______________________________________________
> atoca mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/atoca

---

From: "'Mark Wood'" <[email-masked]>
Date: Sat, 21 Jul 2012 14:12:09 +0100

I Repeat;

The matter of using public networks for authority to citizen communication
is only just now becoming a mainstream topic. We just did not have a model
for such before the deployment of ETWS in Japan and now CMAS in the USA in
2012.

Now that we do have such systems is the time to address the matter.

I deduce that anyone wanting to obtain a licence for a public mobile network
will have to have some sort of method of realising the same burdens that are
now placed on the cellular network providers. The wording of the
requirements will probably be non technology dependent, so the same burdens
will be a requirement for all system technologies. 

We have not had this conversation yet, and we need to have it now that
CMAS/ETSI has finally just arrived (after a long gestation period).

It will probably take at least another year to understand what the issues
are before we can make any submissions to the IETF.

Mark wood DRCF.

---

From: Peter Saint-Andre <[email-masked]>
Date: Sat, 21 Jul 2012 10:01:11 -0600

> are before we can make any submissions to the IETF.

In which case perhaps it's appropriate to close the WG and pursue this
work, if it emerges at all, through individual Internet-Drafts.

Peter

-- 
Peter Saint-Andre
https://stpeter.im/

---

From: Art Botterell <[email-masked]>
Date: Sat, 21 Jul 2012 10:41:27 -0700

Mark makes the essential point, IMHO.  This working group may simply have been ahead of its time.  So if the WG format isn't appropriate... I don't really have an opinion on that... I hope we can find some way to keep a less formal conversation going among folks who are interested, in anticipation that relevant issues may come clear over the next few years.

- Art

---

From: Tony Rutkowski <[email-masked]>
Date: Sat, 21 Jul 2012 16:30:03 -0400

Hi Art,

Good admonitions.

As someone who participates significantly in the
MILE group (ironically dealing with incidents),
I'm curious if anyone has contemplated treating
an emergency warning message as simply a
specialized instance of incident messages,
and potentially using IODEF SCI to move
CAP messages under that aegis?

There is a certain irony in Q4/17 (from which
I'm about to depart), that they are both within
that same group.

best,
tony

---

From: Art Botterell <[email-masked]>
Date: Sat, 21 Jul 2012 14:02:22 -0700

Tony, I've always thought of CAP as an instance of an event message, as distinguished from a state message (e.g., a SITREP).  Can't say I've belabored the distinction, but in general I think an event message is mainly meaningful in terms of when it arrives, while a state message is more meaningful as a snapshot from the time it was sent.  (Rare, of course, is the pure example of either class.)

I'll leave it to smarter folks to draw that line more clearly, but I've seen a number of instances where system-level conversations got confused because some folks were using an eventing model and other folks were thinking in terms of a representation of system state.

Anyway, seems like we're getting a lot of topical silos that are all trying to either, a) trigger activity somewhere else (frequently with some situational context), or b) offer information about some state of affairs (perhaps implying a particular call-to-action, but more often not.)

- Art

---

From: "Mark" <[email-masked]>
Date: Sat, 21 Jul 2012 22:07:05 +0100

Hi Guys,

The features that make an emergency Public Warning Messaging special are; 

1 the super-massive scale of the broadcast 
(Maybe to 10s of millions of hosts)
 
2 in a handful of seconds 
(CMAS takes only 7 seconds to deliver them all),
 
3 during extreme overload, 
(CMAS uses out of band signalling)
 
4 without any foreknowledge of their addresses, 
(No data base needed by CMAS)
 
5 and in a completely stateless passive way, 
(No TCP session exhaustion possible)
 
6 which is geo specific, 
(CMAS is selective down to one cell, about 1 mile)
 
7 Must be highly resistant to Slashdot or DOS events. 
(Disasters are always without exception accompanies by Tsunami waves of
load). 

Very extensive studies carried out by both government and industry showed
that the most appropriate way of dealing with these very extreme events is
to use passive point-to-multipoint bearer services. For example in the
cellular networks, Cell Broadcast and multi media Broadcast multicast are
such bearers. This is why they had to be deployed for this special
situation. The studies were very thorough, and completely conclusive.

The closest equivalent to cell broadcast in IP is IPMulticast.  

These situations are not at all the same as the situation where CAP messages
are being signalled between relatively small numbers of well known systems
which are in a trusted relationship with each other, and there is 'stateful'
handshake relationship between hosts. This is why IMHO a completely
different philosophy is needed, and one which I don't think ATOCA have
looked at in depth yet. 

However the title of the WG clearly indicates that we should, and so as Art
says, the reality on the ground has only just this year caught up with the
subject. Well we WERE ahead of the subject, but not now!

IMHO there is work to do and we have not done it yet :-)

Mark Wood DRCF.

---

From: "DRAGE, Keith (Keith)" <[email-masked]>
Date: Mon, 23 Jul 2012 03:34:01 +0200

I'd note that closing the working group and closing the mailing list are not one and the same thing. 

Mailing lists can exist without the continuation of the working group.

So as and when interest does arise, and activity on the mailing list identifies this, either drafts can be discussed and prepared for individual submission, or a new working group can be chartered and the work resumed as chartered activity.

Keith

> Art Botterell
> Sent: 21 July 2012 18:41
> Subject: Re: [atoca] The future of atoca
> 
> Mark makes the essential point, IMHO.  This working group may simply have
> been ahead of its time.  So if the WG format isn't appropriate... I don't
> really have an opinion on that... I hope we can find some way to keep a
> less formal conversation going among folks who are interested, in
> anticipation that relevant issues may come clear over the next few years.
> 
> - Art
> 
>

---

From: Brian Rosen <[email-masked]>
Date: Mon, 30 Jul 2012 17:26:17 -0400

I have hesitated to respond to this because I'm part of the problem.  However, here goes:

I think the work of atoca is important.  I think it's VERY important.  We need better tools for authority to citizen alerts.  

We have been unable to muster enough effort.  We need to fix that to be viable.  It may be too late.

So, I will make a pledge:
a) I will contribute a draft in this next cycle
b) I will respond to threads on the list aggressively
c) I will start threads to try to reach consensus on requirements and mechanisms

I ask for others to take the same pledge.

I understand that I, and others, should have already done all of that.  Guilty.  I will understand if it is decided that we had our chance and lost it by inactivity.  But I will ask for another chance to get good work done.

Brian

---

From: Hannes Tschofenig <[email-masked]>
Date: Mon, 30 Jul 2012 14:36:45 -0700

The problem I see is that we actually don't have a proposal that actually works.
Abstract discussions about potential solutions don't help to make progress.

---

From: Brian Rosen <[email-masked]>
Date: Mon, 30 Jul 2012 17:43:29 -0400

I don't agree.  I think a lot of what Richard has proposed works.  I think some things could be improved (a draft I will write).  

Brian

---

From: Henning Schulzrinne <[email-masked]>
Date: Mon, 30 Jul 2012 17:46:20 -0400

There is significant regulatory interest in exploring IP-based options, so I would encourage taking stock and looking at a variety of options. Even a summary of the options and why they do NOT work is useful. Some initial questions that push beyond the SIP message space:

One of the bigger problems with CMAS (cellular alerts) is the short message size, which provides only very limited actionable information.

Can we leverage IP-TV style multicast for scalable distribution? How would the equivalent of EAS work in an IP video environment?

Can we separate the common problem of in-area alerting (subscribers in a particular area) from the less-common problem of out-of-area alerting ("elderly relative")?

Do we have any real experience with the realistic limits of web-based flash crowds? If every household is watching entertainment (or Olympic) video at night, the additional load of adding reasonably-detailed information may not be all that large and CDNs are used to large crowds.

Henning

---

From: "Bradner, Scott" <[email-masked]>
Date: Mon, 30 Jul 2012 21:51:42 +0000

I also think the is very important 

but we need to actually have text in front of us to discuss & progress

as a chair, I am willing to keep trying but there is a limit

Scott

---

From: Hannes Tschofenig <[email-masked]>
Date: Mon, 30 Jul 2012 16:13:07 -0700

As expressed in earlier ATOCA meetings I do not have the same view. 

In earlier meetings I was told that a subscribe - notify mechanism does not work for scalability reason and for that reason  
http://tools.ietf.org/html/draft-rosen-sipping-cap-04 was rejected. 

Then, Richard defined a protocol that was supposed to describe an alternative:
http://tools.ietf.org/html/draft-barnes-atoca-meta-02
http://tools.ietf.org/html/draft-barnes-atoca-delivery-01

A client has to register with the alerting server and most likely has to keep that subscription alive (with frequent retransmissions) to deal with NATs and firewalls. The client can indicate certain language features and other stuff in the request.

Then, it seems that unicast UDP messages are sent to those who have registered. 

Since CAP messages (with S/MIME based signatures) are fairly large (see http://tools.ietf.org/html/draft-barnes-atoca-escape-00) a fragmentation is also added.